About Shallow Ablative Lasers for Acne Scars
An ablative laser actually vaporizes (destroys) an area of tissue. The shallow lasers are normally Erbium devices such the Cutera Pearl and Sciton Contour or Profractional. These lasers come in versions that treat the entirety of the skin and in fractional versions which only treat a small portion of the skin (like aerating a lawn). The advantage of the fractional devices is that they tend to go deeper which treats deeper pathology and significantly decreases both healing time and side effects. Erbium lasers will tend to produce about 30-150 microns of ablations in the full forms and about 600-800 microns in their fractional forms. The fractional version of these lasers can provide nice improvement in acne scarring but have two drawbacks. The first is that even the fractional versions of Erbium lasers do not get to the base of most acne scars and the second is these lasers do not provide as much heat to tissue as a CO2. This heat is necessary to induce remodeling of the tissue that is not ablated and is a major factor in the final outcome that a patient sees in the mirror.
About Deep Ablative Treatments for Acne Scars
Almost all of the lasers currently in this category are CO2 lasers. This is the gold standard in revising acne scarring. The newest devices are fractionated like their more shallow counterparts. There are many devices in this category including, Pixel, Affirm, Dot, Fraxil Re:pair, and Lumenis Active FX and Deep FX. Unfortunately, most of them are grossly underpowered.
Underpowered lasers need to use very long laser pulses to get the same amount of energy into the tissue as a short pulse with a properly powered laser. These long pulses can lead to excessive tissue heating and side effects such as discoloration and even scarring. These underpowered devices are cheap to build and more affordable to purchase so they have become very common in the medi-spa industry. I will only go into detail about the appropriately powered devices such as the Lumenis Active FX, Deep FX, and Fraxil Re:pair.
These devices can penetrate 2000 microns into the skin or more and thus are the only devices that can reach the entire scar region. Although good results can be obtained with both devices the clear king of the mountain is the Lumenis laser. In a study done a Johns Hopkins 9 out 10 patients preferred both the procedure and results from the Active FX when compared to the Fraxil Re:pair.
Other Acne Scar Treatments:
There are many other treatments including subcision, needling, punching out lesions, and adding filler that can all be used to improve the texture of acne scarring. Although these modalities can be effective, they tend to be more useful for less extensive lesions.